The economic crisis and raw politics threatened to derail the first presidential debate as John McCain challenged Barack Obama to delay Friday's forum and join forces to help Washington fix the financial mess. Obama rebuffed his GOP rival, saying the next president needs to "deal with more than one thing at once."

The White House rivals maneuvered to claim the leadership role in resolving the economic turmoil that has overshadowed their campaign six weeks before Election Day. Obama said he would proceed with his debate preparations while consulting with bailout negotiators and Treasury Secretary Henry Paulson. McCain said he would stop all advertising, fundraising and other campaign events to return to Washington and work for a bipartisan solution.

"It's my belief that this is exactly the time when the American people need to hear from the person who, in approximately 40 days, will be responsible for dealing with this mess," Obama said at a news conference in Clearwater, Fla. "It's going to be part of the president's job to deal with more than one thing at once."

But McCain said they must focus on a bipartisan solution to the nation's financial woes as the Bush administration's $700 billion bailout proposal seemed headed for defeat. If not, McCain said ominously, credit will dry up, people will no longer be able to buy homes, life savings will be at stake and businesses will not have enough money to pay workers.

"It has become clear that no consensus has developed to support the administration's proposal," McCain said. "I do not believe that the plan on the table will pass as it currently stands, and we are running out of time."

Sen. Lindsey Graham, McCain's representative in debate negotiations, said McCain will not attend the debate "unless there is an agreement that would provide a solution" to the financial crisis. Graham (R-S.C.) told The Associated Press that the agreement would have to be publicly endorsed by Obama, McCain, the White House and congressional leaders, but not necessarily given final passage by the House and Senate.

Asked whether the debate could go forward if McCain doesn't show, Obama spokesman Robert Gibbs replied, "My sense is there's going to be a stage, a moderator, an audience and at least one presidential candidate."

Their competing positions came after the two senators spoke privately, each trying to portray himself as the bipartisan leader in a time of crisis.

McCain beat Obama to the punch with the first public statement. He said he had spoken to President Bush and asked him to convene a leadership meeting in Washington that would include him and Obama.

Even as McCain said he was putting the good of the country ahead of politics, his surprise announcement was clearly political. It was an attempt to try to outmaneuver Obama on an issue in which he's trailing, the economy, as the Democrat gains in polls. He quickly went before TV cameras minutes after speaking with Obama and before the two campaigns had hammered out a joint statement expressing that Congress should act urgently on the bailout.

And while McCain's camp said he would "suspend" his campaign, it simply will move to Washington knowing the spotlight will remain on him no matter where he is.

Obama, too, made a political calculation by rejecting McCain's challenge while trying to still appear on top of the problem. Obama repeatedly stressed at his news conference that he called McCain first to propose that they issue a joint statement in support of a package to help fix the economy as soon as possible. He said McCain called back several hours later, as Obama was leaving a rally in Florida, and agreed to the idea of a statement but also said he wanted to postpone the debate and hold joint meetings in Washington.

Obama said he suggested they first issue a joint statement showing bipartisanship.

"When I got back to the hotel, he had gone on television to announce what he was going to do," Obama said.

McCain said he would return to Washington after addressing former President Clinton's Global Initiative session in New York Thursday. He canceled his planned appearance today on CBS' "Late Show With David Letterman" program and a meeting with the prime minister of India.

McCain called Senate Democratic Leader Harry Reid and House Speaker Nancy Pelosi to propose that joint meetings with Obama and congressional leadership be held quickly, according to leadership aides. Reid spokesman Jim Manley said Reid responded by reading McCain his public statement, in which he said it would not be helpful to have the candidates come back during negotiations and inject presidential politics.

The Commission on Presidential Debates and the University of Mississippi, the site of the forum, said they were moving forward with plans for the debate.

McCain's running mate, Sarah Palin, was canceling her limited campaign events. Palin said in an interview with CBS Evening News today that the country could be headed for another Great Depression if Congress doesn't reach a solution.

Scores of congressional Republicans have hinted this week they may oppose the proposed $700 billion bailout even though it is Bush's priority. Reid (D-Nev.) pointedly suggested that Democratic lawmakers could not be expected to back it if McCain did not publicly do so.

That leaves McCain with two unpalatable choices. He can oppose a major Republican initiative that the administration says is essential to preventing a full-blown recession, and risk heavy blame if the prediction comes true. Or he can vote for an extraordinarily costly bailout, which many Americans seem to resent, just when polls show him falling farther behind Obama.

Several GOP lawmakers and strategists said they see no way that McCain can oppose the main elements of the bailout plan and present himself as a bold leader. He must say, "we need to get this done for the future of our country," said John Feehery, a former aide to top Republican lawmakers. "Country first," Feehery said, noting McCain's campaign slogan.

Of course, Obama also risks angry voter reactions if he supports the bailout plan. But he could frame his stand as bipartisan statesmanship, whereas McCain's vote could be spun as another example of his siding with Bush, a major impediment to his campaign.